My horse who is prone to scratches on his white legs has recently started losing chunks of tail hair high up on his dock, and not by rubbing and it's not getting bitten out or chewed off. It's not losing hair during grooming though so I don't know if it's somehow getting yanked out? It is short hair high on his dock, about 4" max.
My first thought is of course fungus so I have washed it with an antifungal/antibacterial wash and have been applying Eqyss antifungal gel on it with little avail. It is not ichy either..
Now I am thinking it could be selenium? He has recently had his RB bumped up to 4 lbs from 2 lbs per day and that would include just under 2.5 mg of selenium (total in the 4 lbs). He has been on 3-4lbs previously without issue and is well under the "high" limit for my area of 0.5 ppm for selenium supplementation. So not likely and he is not showing any other signs of selenium toxicity?? Right?? I hope..
Any ideas for the tail fungus or is he actually being over supplemented for selenium?? Any other ideas as to why he is losing tail??